In a method for correcting amplitude and phase offsets in a sigma-delta modulator having a loop including an integrator with a filter and an amplifier, an analog-to-digital converter, a digital-to-analog converter, and an adder-subtractor, an open-loop amplitude/phase frequency response of the modulator is estimated digitally. A phase offset value and an amplitude offset value are calculated by comparing the estimated open-loop amplitude/phase response with a reference amplitude/phase frequency response. The phase and gain offsets of the loop are then compensated for according to the estimated offset values. A sigma-delta modulator implements the method.
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